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* [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer.
@ 2006-01-16 20:00 fabien dot chene at laposte dot net
2006-01-16 20:06 ` [Bug c++/25811] " pinskia at gcc dot gnu dot org
` (12 more replies)
0 siblings, 13 replies; 14+ messages in thread
From: fabien dot chene at laposte dot net @ 2006-01-16 20:00 UTC (permalink / raw)
To: gcc-bugs
$ cat podnew.cpp
struct Foo // POD
{
double const d;
};
int main()
{
Foo* foo = new Foo; // without the new-initializer
}
This simple code does not fail to compile.
According to the standard (5.3.4.15), I am not sure, but i think it should fail
to compile.
$ g++ podnew.cpp && echo "no failure"
no failure
I use gcc-4.0.2, but it is the same behaviour with 3.4.4.
$ g++ -v
Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: /var/tmp/portage/gcc-4.0.2-r1/work/gcc-4.0.2/configure
--prefix=/usr --bindir=/usr/i686-pc-linux-gnu/gcc-bin/4.0.2
--includedir=/usr/lib/gcc/i686-pc-linux-gnu/4.0.2/include
--datadir=/usr/share/gcc-data/i686-pc-linux-gnu/4.0.2
--mandir=/usr/share/gcc-data/i686-pc-linux-gnu/4.0.2/man
--infodir=/usr/share/gcc-data/i686-pc-linux-gnu/4.0.2/info
--with-gxx-include-dir=/usr/lib/gcc/i686-pc-linux-gnu/4.0.2/include/g++-v4
--host=i686-pc-linux-gnu --build=i686-pc-linux-gnu --disable-altivec
--enable-nls --without-included-gettext --with-system-zlib --disable-checking
--disable-werror --disable-libunwind-exceptions --disable-multilib
--disable-libgcj --enable-languages=c,c++,f95 --enable-shared
--enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu
Thread model: posix
gcc version 4.0.2 (Gentoo 4.0.2-r1, pie-8.7.8)
--
Summary: No failure creating a POD containing a const member,
using new without a new-initializer.
Product: gcc
Version: 4.0.2
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: fabien dot chene at laposte dot net
GCC build triplet: i686-pc-linux-gnu
GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
@ 2006-01-16 20:06 ` pinskia at gcc dot gnu dot org
2010-03-30 8:22 ` fabien dot chene at gmail dot com
` (11 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-01-16 20:06 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from pinskia at gcc dot gnu dot org 2006-01-16 20:06 -------
Confirmed, not a regression.
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Keywords| |accepts-invalid
Known to fail| |2.95.3 3.3.1 3.0.4 3.4.0
| |4.0.0 4.1.0 4.2.0
Last reconfirmed|0000-00-00 00:00:00 |2006-01-16 20:06:02
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
2006-01-16 20:06 ` [Bug c++/25811] " pinskia at gcc dot gnu dot org
@ 2010-03-30 8:22 ` fabien dot chene at gmail dot com
2010-03-30 9:16 ` redi at gcc dot gnu dot org
` (10 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-30 8:22 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from fabien dot chene at gmail dot com 2010-03-30 08:22 -------
is it still invalid in c++0X ?
5.3.4.15 has been revamped, and I no longer find a motif to reject such code.
I think the following code is also invalid, according to 8.5.6 (c++03) / 8.5.8
(c++0x):
struct A { int& i; };
void f () { new A; }
I have a patch to fix both issues.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
2006-01-16 20:06 ` [Bug c++/25811] " pinskia at gcc dot gnu dot org
2010-03-30 8:22 ` fabien dot chene at gmail dot com
@ 2010-03-30 9:16 ` redi at gcc dot gnu dot org
2010-03-30 10:07 ` fabien dot chene at gmail dot com
` (9 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: redi at gcc dot gnu dot org @ 2010-03-30 9:16 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from redi at gcc dot gnu dot org 2010-03-30 09:16 -------
(In reply to comment #2)
> is it still invalid in c++0X ?
Yes.
> 5.3.4.15 has been revamped, and I no longer find a motif to reject such code.
In C++0x the object is default-initialized, which for a class type means the
default constructor is called. In this code, the default constructor is
deleted, so the code will not compile. See 12.1/5
> I think the following code is also invalid, according to 8.5.6 (c++03) / 8.5.8
> (c++0x):
>
> struct A { int& i; };
> void f () { new A; }
Not quite: in C++0x the program doesn't call for default-initialization of
A::i, it calls for default-initialization of A, which is invalid because the
default constructor is deleted.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (2 preceding siblings ...)
2010-03-30 9:16 ` redi at gcc dot gnu dot org
@ 2010-03-30 10:07 ` fabien dot chene at gmail dot com
2010-03-30 10:10 ` fabien dot chene at gmail dot com
` (8 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-30 10:07 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from fabien dot chene at gmail dot com 2010-03-30 10:07 -------
(In reply to comment #3)
> (In reply to comment #2)
> > is it still invalid in c++0X ?
>
> Yes.
>
> > 5.3.4.15 has been revamped, and I no longer find a motif to reject such code.
>
> In C++0x the object is default-initialized, which for a class type means the
> default constructor is called. In this code, the default constructor is
> deleted, so the code will not compile. See 12.1/5
OK thanks.
> > I think the following code is also invalid, according to 8.5.6 (c++03) / 8.5.8
> > (c++0x):
> >
> > struct A { int& i; };
> > void f () { new A; }
>
> Not quite: in C++0x the program doesn't call for default-initialization of
> A::i, it calls for default-initialization of A, which is invalid because the
> default constructor is deleted.
OK, but it appears that the C++0X part is not yet implemented in GCC -- the
constructor is not deleted in this case.
Nevertheless, can you confirm that it is valid C++03 ?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (3 preceding siblings ...)
2010-03-30 10:07 ` fabien dot chene at gmail dot com
@ 2010-03-30 10:10 ` fabien dot chene at gmail dot com
2010-03-30 11:19 ` redi at gcc dot gnu dot org
` (7 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-30 10:10 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from fabien dot chene at gmail dot com 2010-03-30 10:10 -------
> Nevertheless, can you confirm that it is valid C++03 ?
I mean invalid, sorry.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (4 preceding siblings ...)
2010-03-30 10:10 ` fabien dot chene at gmail dot com
@ 2010-03-30 11:19 ` redi at gcc dot gnu dot org
2010-03-31 7:07 ` fabien dot chene at gmail dot com
` (6 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: redi at gcc dot gnu dot org @ 2010-03-30 11:19 UTC (permalink / raw)
To: gcc-bugs
------- Comment #6 from redi at gcc dot gnu dot org 2010-03-30 11:19 -------
(In reply to comment #5)
> > Nevertheless, can you confirm that it is valid C++03 ?
>
> I mean invalid, sorry.
Yup :-)
It is invalid. A is a non-POD class type, so 5.3.4/15 says the new-expression
without a new-initializer causes the object to be default-initialized, which
causes a default constructor to be implicitly-defined with an empty
mem-initializer list (12.1/7) which is ill-formed by 8.5/5 because the
reference member is not initialized.
In C++03 the cases of Foo and A are slightly different, "new Foo" is ill-formed
according to 5.3.4/15 and "new A" is ill-formed as described above.
In C++0x both "new Foo" and "new A" result in a call to a deleted constructor.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (5 preceding siblings ...)
2010-03-30 11:19 ` redi at gcc dot gnu dot org
@ 2010-03-31 7:07 ` fabien dot chene at gmail dot com
2010-03-31 8:55 ` redi at gcc dot gnu dot org
` (5 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-31 7:07 UTC (permalink / raw)
To: gcc-bugs
------- Comment #7 from fabien dot chene at gmail dot com 2010-03-31 07:06 -------
(In reply to comment #6)
> (In reply to comment #5)
> > > Nevertheless, can you confirm that it is valid C++03 ?
> >
> > I mean invalid, sorry.
>
> Yup :-)
>
> It is invalid. A is a non-POD class type, so 5.3.4/15 says the new-expression
> without a new-initializer causes the object to be default-initialized, which
> causes a default constructor to be implicitly-defined with an empty
> mem-initializer list (12.1/7) which is ill-formed by 8.5/5 because the
> reference member is not initialized.
>
>
> In C++03 the cases of Foo and A are slightly different, "new Foo" is ill-formed
> according to 5.3.4/15 and "new A" is ill-formed as described above.
Thanks for the clarification !
Patch here for the non C++0X part:
http://gcc.gnu.org/ml/gcc-patches/2010-03/msg01467.html
> In C++0x both "new Foo" and "new A" result in a call to a deleted constructor.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (6 preceding siblings ...)
2010-03-31 7:07 ` fabien dot chene at gmail dot com
@ 2010-03-31 8:55 ` redi at gcc dot gnu dot org
2010-03-31 12:21 ` fabien dot chene at gmail dot com
` (4 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: redi at gcc dot gnu dot org @ 2010-03-31 8:55 UTC (permalink / raw)
To: gcc-bugs
------- Comment #8 from redi at gcc dot gnu dot org 2010-03-31 08:55 -------
(N.B. your email to gcc-patches gives the wrong PR number in the subject.)
This reject the following valid program:
struct X {
X() : c(0), r(c) {}
const int c;
int const& r;
};
int main()
{
new X;
}
If there is a default constructor it will be called, and so the members will
not be uninitialized.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (7 preceding siblings ...)
2010-03-31 8:55 ` redi at gcc dot gnu dot org
@ 2010-03-31 12:21 ` fabien dot chene at gmail dot com
2010-03-31 12:34 ` redi at gcc dot gnu dot org
` (3 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-31 12:21 UTC (permalink / raw)
To: gcc-bugs
------- Comment #9 from fabien dot chene at gmail dot com 2010-03-31 12:20 -------
(In reply to comment #8)
> (N.B. your email to gcc-patches gives the wrong PR number in the subject.)
>
> This reject the following valid program:
>
> struct X {
> X() : c(0), r(c) {}
> const int c;
> int const& r;
> };
>
> int main()
> {
> new X;
> }
>
> If there is a default constructor it will be called, and so the members will
> not be uninitialized.
OK, I've revised the patch to check for a user defined constructor.
I have also added your testcase, and others dealing with arrays.
http://gcc.gnu.org/ml/gcc-patches/2010-03/msg01486.html
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (8 preceding siblings ...)
2010-03-31 12:21 ` fabien dot chene at gmail dot com
@ 2010-03-31 12:34 ` redi at gcc dot gnu dot org
2010-03-31 13:46 ` fabien dot chene at gmail dot com
` (2 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: redi at gcc dot gnu dot org @ 2010-03-31 12:34 UTC (permalink / raw)
To: gcc-bugs
------- Comment #10 from redi at gcc dot gnu dot org 2010-03-31 12:34 -------
Thanks. I can't test it now but that looks better.
Just below your new code I see this error:
error ("uninitialized const in %<new%> of %q#T", elt_type);
Maybe your new diagnostics should also include 'new' like that.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (9 preceding siblings ...)
2010-03-31 12:34 ` redi at gcc dot gnu dot org
@ 2010-03-31 13:46 ` fabien dot chene at gmail dot com
2010-03-31 13:53 ` redi at gcc dot gnu dot org
2010-04-12 19:58 ` jason at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: fabien dot chene at gmail dot com @ 2010-03-31 13:46 UTC (permalink / raw)
To: gcc-bugs
------- Comment #11 from fabien dot chene at gmail dot com 2010-03-31 13:46 -------
(In reply to comment #10)
> Thanks. I can't test it now but that looks better.
>
> Just below your new code I see this error:
>
> error ("uninitialized const in %<new%> of %q#T", elt_type);
>
> Maybe your new diagnostics should also include 'new' like that.
Would 'error ("uninitialized const member in %q#T using %<new%>", elt_type)'
suit you ?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (10 preceding siblings ...)
2010-03-31 13:46 ` fabien dot chene at gmail dot com
@ 2010-03-31 13:53 ` redi at gcc dot gnu dot org
2010-04-12 19:58 ` jason at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: redi at gcc dot gnu dot org @ 2010-03-31 13:53 UTC (permalink / raw)
To: gcc-bugs
------- Comment #12 from redi at gcc dot gnu dot org 2010-03-31 13:52 -------
That works for me, although I should point out I can't approve the patch, so
it's just my opinion
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug c++/25811] No failure creating a POD containing a const member, using new without a new-initializer.
2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
` (11 preceding siblings ...)
2010-03-31 13:53 ` redi at gcc dot gnu dot org
@ 2010-04-12 19:58 ` jason at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: jason at gcc dot gnu dot org @ 2010-04-12 19:58 UTC (permalink / raw)
To: gcc-bugs
------- Comment #13 from jason at gcc dot gnu dot org 2010-04-12 19:58 -------
Subject: Bug 25811
Author: jason
Date: Mon Apr 12 19:58:27 2010
New Revision: 158239
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158239
Log:
PR c++/25811
* cp-tree.h (diagnose_uninitialized_cst_or_ref_member): Declare.
* init.c (build_new_1): Check for uninitialized const members and
uninitialized reference members, when using new without
new-initializer. Call diagnose_uninitialized_cst_or_ref_member.
(diagnose_uninitialized_cst_or_ref_member): Define, call
diagnose_uninitialized_cst_or_ref_member_1.
(diagnose_uninitialized_cst_or_ref_member_1): New function.
Added:
trunk/gcc/testsuite/g++.dg/init/pr25811.C
Modified:
trunk/gcc/cp/ChangeLog
trunk/gcc/cp/cp-tree.h
trunk/gcc/cp/init.c
trunk/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25811
^ permalink raw reply [flat|nested] 14+ messages in thread
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2006-01-16 20:00 [Bug c++/25811] New: No failure creating a POD containing a const member, using new without a new-initializer fabien dot chene at laposte dot net
2006-01-16 20:06 ` [Bug c++/25811] " pinskia at gcc dot gnu dot org
2010-03-30 8:22 ` fabien dot chene at gmail dot com
2010-03-30 9:16 ` redi at gcc dot gnu dot org
2010-03-30 10:07 ` fabien dot chene at gmail dot com
2010-03-30 10:10 ` fabien dot chene at gmail dot com
2010-03-30 11:19 ` redi at gcc dot gnu dot org
2010-03-31 7:07 ` fabien dot chene at gmail dot com
2010-03-31 8:55 ` redi at gcc dot gnu dot org
2010-03-31 12:21 ` fabien dot chene at gmail dot com
2010-03-31 12:34 ` redi at gcc dot gnu dot org
2010-03-31 13:46 ` fabien dot chene at gmail dot com
2010-03-31 13:53 ` redi at gcc dot gnu dot org
2010-04-12 19:58 ` jason at gcc dot gnu dot org
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